//==============================================================================
//	
//	Copyright (c) 2002-
//	Authors:
//	* Dave Parker <d.a.parker@cs.bham.ac.uk> (University of Birmingham/Oxford)
//	
//------------------------------------------------------------------------------
//	
//	This file is part of PRISM.
//	
//	PRISM is free software; you can redistribute it and/or modify
//	it under the terms of the GNU General Public License as published by
//	the Free Software Foundation; either version 2 of the License, or
//	(at your option) any later version.
//	
//	PRISM is distributed in the hope that it will be useful,
//	but WITHOUT ANY WARRANTY; without even the implied warranty of
//	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//	GNU General Public License for more details.
//	
//	You should have received a copy of the GNU General Public License
//	along with PRISM; if not, write to the Free Software Foundation,
//	Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//	
//==============================================================================

package com.prism.e4.rcp.explicit;

import java.util.BitSet;
import java.util.List;

import com.prism.e4.rcp.prism.PrismComponent;
import com.prism.e4.rcp.prism.PrismException;

/**
 * Abstract class for (explicit) classes that compute (M)ECs, i.e. (maximal) end
 * components, for a nondeterministic model such as an MDP.
 */
public abstract class ECComputer extends PrismComponent {
	/**
	 * Static method to create a new ECComputer object, depending on current
	 * settings.
	 */
	public static ECComputer createECComputer(PrismComponent parent,
			NondetModel model) throws PrismException {
		// Only one algorithm implemented currently
		return new ECComputerDefault(parent, model);
	}

	/**
	 * Base constructor.
	 */
	public ECComputer(PrismComponent parent) throws PrismException {
		super(parent);
	}

	/**
	 * Compute states of maximal end components (MECs) and store them. They can
	 * be retrieved using {@link #getMECStates()}.
	 */
	public abstract void computeMECStates() throws PrismException;

	/**
	 * Compute states of all maximal end components (MECs) in the submodel
	 * obtained by restricting this one to the set of states {@code restrict},
	 * and store them. They can be retrieved using {@link #getMECStates()}.
	 * 
	 * @param restrict
	 *            BitSet for the set of states to restrict to.
	 */
	public abstract void computeMECStates(BitSet restrict)
			throws PrismException;

	/**
	 * Get the list of states for computed MECs.
	 */
	public abstract List<BitSet> getMECStates();
}

// ------------------------------------------------------------------------------